1. Field of the Invention
The present invention relates to providing audiovisual content on a network, and methods of transferring the audiovisual content between devices attached to the network.
2. Description of the Related Art
It is now common for people to have access to wide range of audiovisual content. Audiovisual content or media includes, but is not limited to, content such as music, films and television programming. The content may either be available on a form of physical storage media, such as an optical disc or a hard drive, or available ‘live’ or in ‘real time’ via broadcasting services such as television, radio, the interne or on-demand services.
As audiovisual content becomes available from more sources and in more formats, it becomes difficult for a user to organise and access the content as freely as they might wish. For example, in a home environment, some content may be stored on a personal computer (a PC) in one room, whilst a hi-fi system capable of playing music may be located in another room and a television for playing broadcast programming may be located in another room. Therefore, a user will have to go to the different rooms to access the different sorts of content.
However, a user may desire to watch a film which is recorded on the hard drive of the PC via the television. For example, the television may provide a larger viewing screen than the PC or simply be in a more convenient location. In such situations, it is desirable to provide a network connecting the various pieces of audiovisual equipment and storage, so that the content at one physical location on the network may be accessed by any appropriate device at any other physical location on the network.
A known way of providing a network is to use the Universal Plug and Play (UPnP) protocol for communicating between devices on the network. Universal Plug and Play (UPnP) extends the simplicity of Device Plug and Play (common in the PC environment) to include the entire network, enabling discovery and control of devices, including networked devices and services, such as network-attached printers, Internet gateways, and consumer electronics equipment. It is designed to support zero-configuration, “invisible” networking, and automatic discovery for a breadth of device categories from a wide range of vendors.
With UPnP, a device can dynamically join a network, obtain an IP address, convey its capabilities, and learn about the presence and capabilities of other devices—all automatically; enabling zero configuration networks. Devices can subsequently communicate with each other directly; thereby further enabling peer to peer networking.
UPnP is an open standard and uses standard TCP/IP and Internet protocols, enabling it to seamlessly fit into existing networks. Because UPnP is a distributed, open network architecture, defined by the protocols used, it is independent of any particular operating system, programming language, or physical medium (just like the Internet). UPnP does not specify the APIs applications will use, allowing operating system vendors to create the APIs that will meet their customer needs.
Building on this platform, the Digital Living Network Alliance (DLNA) standard has been developed, with a specific focus on ensuring compatibility between consumer electronics.
However, although the existing UPnP and DLNA protocols go some way to easing a user's access to audiovisual content on a network, there is still room for improvement.
One problem that a user may face is that they may start viewing or listening to content at one location, and then either be interrupted or simply wish to change location. For example, a user may start watching a film in their living room, but then wish to continue watching the film in their kitchen whilst they prepare dinner. At present, this cannot easily be achieved. If the film is a recording, it may be possible to access the recording from a television in the kitchen, but this requires the user to start playback again in the kitchen, and then locate their playback position in the film. If the film is broadcast content, the user may miss part of the broadcast as they change rooms. Also, if the television device in the kitchen is off, it may take time to re-connect to the network and access the desired content. All of these issues mean that a user's enjoyment of the content is impaired, as it is difficult to transfer content between devices mid-way through content playback.
WO-A-2006/090340 seeks to provide a method for extending the capabilities of UPnP AV network architecture with a “Universal Follow-me” functionality. This functionality allows users to pause or stop playing media content at one location on the network and resume the playing of the media content at a later point in time at a different or the same location without a loss of continuity. However, the method simply stores the playback position in connection with the media content. At the later point in time, the user still has to locate the media he wishes to view. As such, the “follow-me” functionality is mis-named, because the media does not follow the user. Rather, the user has to “summon” the media from the new location. This still leaves a burden on the user to access the media, which is especially annoying if the change in location is not accompanied by a long pause (such as when a user changes rooms).